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When to Plant Impatiens in USDA Zone 10b

Zone 10b Zone 10b June

Your June planting checklist for Zone 10b

If you only do a handful of things in the garden this June, make it these. They're sequenced around your zone's frost timing.

Avg. last frost February 13
Avg. first frost November 27
  1. Basket week: impatiens

    Don't tug. Use scissors or pruners for clean cuts — torn stems invite disease.

To set up a strong July, finish these tasks
  • First harvests: impatiens
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Impatiens (Impatiens walleriana) are the go-to annual for shaded beds and containers. They produce a continuous carpet of flat-faced blooms from transplant until frost, needing little deadheading. Their preference for consistent moisture and part-shade makes them ideal under trees and along north-facing borders.

In Zone 10b, the average last spring frost is around January 1 and the first fall frost is around December 31, giving you a growing season of approximately 364 days.

Annual Blooms in Summer Pollinator-friendly
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Zone 10b Year-round
365 days
Last Spring Frost No frost
365 growing days
First Fall Frost No frost

Impatiens Planting Timeline — Zone 10b

Where Is USDA Zone 10b?

The map below highlights the states that contain Zone 10b. Click any state to see the Impatiens planting schedule for that location.

Prints a clean, ink-friendly version without maps or navigation.

Impatiens Planting Calendar — Zone 10b

Activity When Date Range
Start Indoors November 6 Nov 6 – Nov 20
Transplant Outdoors November 20 Nov 20 – Dec 4
Bloom January 29 Jan 29 – Aug 27

· 10" apart · Rows 12" apart

Month-by-Month Timeline

MonthActivities
January Bloom
February Bloom
March Bloom
April Bloom
May Bloom
June Bloom
July Bloom
August Bloom
September
October
November Start Indoors Transplant Outdoors
December Transplant Outdoors

Free Zone 10b Planting Calendar PDF

Know exactly when to plant every crop in your zone. Get a printable month-by-month calendar customized for Zone 10b with start dates, transplant windows, and harvest times.

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Growing Conditions

Sun

Partial Shade (3-6 hours)

💧 Water

Moderate — regular watering

Days to Maturity

60–75 days

Soil pH

6 – 6.5

Zone Temperature Range

35°F to 40°F average annual minimum

Growing Season

365 days (Zone 10b average)

Planting Specifications

Plant Spacing10 inches apart
Row Spacing12 inches between rows

Succession Planting Impatiens in Zone 10b

7
successive plantings in Zone 10b's ~365-day season

Sow every 6.9 weeks for continuous harvest throughout the season.

Growing Tips for Impatiens in Zone 10b

Zone 10b offers a long growing season (~365 days). You can plant Impatiens earlier and may get multiple harvests.

Start seeds indoors 8–10 weeks before last frost at 70–75°F; germination requires light — do not cover seeds. Transplant after last frost once nights consistently exceed 50°F. Water regularly — wilting causes bud drop and they rarely fully recover the same flush. Watch for impatiens downy mildew (IDM); consider New Guinea impatiens as a resistant alternative in affected regions. Pinch tips at planting to encourage branching.

Companion Planting

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Saving Impatiens Seeds

Recommended for Your Garden

☀️
Garden Shade Cloth $15-35

Reduce heat stress and sun scorch in hot climates with UV-stabilized shade cloth.

🌱
Seed Starting Trays $8-20

Start seeds indoors with reusable cell trays and humidity domes.

🧪
Soil Test Kit $12-25

Test your soil pH, nitrogen, phosphorus, and potassium levels before planting.

Related Plants

Frequently Asked Questions

When should I plant Impatiens in Zone 10b?

In Zone 10b, plan your Impatiens planting around the average last frost date of January 1. Start seeds indoors around November 6. Transplant seedlings around November 20.

Can Impatiens grow in Zone 10b?

Yes, Impatiens can grow well in Zone 10b, hardy in USDA zones 2a through 11b. Zone 10b has a growing season of approximately 364 days, which is sufficient for Impatiens (60-75 days to maturity).

When can I harvest Impatiens in Zone 10b?

In Zone 10b, expect to harvest Impatiens from January 29 – August 27. Impatiens takes 60-75 days from planting to harvest.

What is the last frost date for Zone 10b?

The average last spring frost in Zone 10b is around January 1, and the first fall frost is around December 31. This gives a growing season of approximately 364 days. These are 50% probability dates — actual frost dates vary year to year.

What should I plant next to Impatiens?

Good companion plants for Impatiens include Hostas, Ferns, Caladiums, Begonias. These companions can help with pest control, pollination, and nutrient sharing.

🌱

Your Zone 10b Garden Planner — Free

A 22-page printable planner tailored to Zone 10b. Planting dates, monthly task lists, harvest log, seed inventory, and succession charts — everything you need to plan a full season.

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Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals, University Cooperative Extension planting guides. Planting dates are estimates based on average frost dates — local conditions may vary. Last updated: June 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.